In a communication network, a Connection Termination Point (CTP) refers to a logical end point of a sub-network connection or link connection. A network element, such as a switch, may provide redundancy by configuring one or more CTPs as a protect CTPs, where other CTPs may be referred to as work CTPs. For example, N work CTPs and one protect CTP may be grouped together, where if any one of the work CTPs in the group goes down, the protect CTP may be utilized in place of that work CTP until it is up again.
A Performance Monitoring (PM) record or table may be used to keep track of the performance of a work CTP. A PM record may be needed to ensure that a client is receiving the level of service contracted to the client. For example, a PM record may include such performance data as: UAS-C, unavailable seconds for the circuit (from the equipment); UAS-P, unavailable seconds for the path (from the equipment); SES, severely errored seconds (from the equipment); ES, errored seconds (from the equipment); OSS, out of service seconds, determined by the SLM (Service Layer Manager), which are those seconds where the service is not routed; SS, suspect seconds, from the equipment and the SLM, which are those seconds where the SLM was not able to collect data and/or the data is suspect; and TTS, total time in seconds the circuit was provisioned during the time interval. The above data may be recorded with a granularity of 15-minute bins or time intervals.
In a protection group, there are PM records for each CTP, where the performance counters run continuously. This allows the monitoring of each CTP individually where a work CTP will have its own PM record and a protect CTP will have its own PM record. However, from the PM records of the work and protect CTPs alone, it is difficult to measure the service disrupt time when any switching or mesh activities occur with respect to the circuit under consideration. It is expected that obtaining such data at the SLM level will lead to inaccurate performance determination.